1. Field of the Invention
The present invention relates to a pellet conveying device which can be used in a die (pellet) bonding apparatus, a pellet jig loading device, etc.
2. Prior Art
In a die bonding apparatus, as well known, dies (pellets) on a pick-up stage are, for example, suction-chucked, picked up and conveyed to a bonding stage by a collet; and then the dies are bonded to a lead frame, substrate, etc. on the die bonding stage. Accordingly, the die bonding apparatus requires a raising and lowering mechanism, which raises and lowers the collet, and a reciprocating motion mechanism, which moves the collet back and forth between the pick-up stage and the bonding stage.
The following apparatuses are known as conventional types of die bonding apparatuses: In the first type, the raising and lowering motions of the collet are accomplished using a cam, and the reciprocating movement of the collet is accomplished by moving an XY table, on which the entire apparatus is mounted, in the X and Y directions. This type of bonding apparatus is disclosed in Japanese Patent Application Laid-Open (Kokai) No. 57-122535 and Japanese Patent Application Publication (Kokoku) No. 3-40502. In the second type of the bonding apparatus, the raising and lowering motion of the collet are accomplished by using a cam to raise and lower the entire apparatus, and the reciprocating movement of the collet is accomplished by pivoting a conveying arm which holds the collet.
In the first type of bonding apparatus, the reciprocating movement of the collet is accomplished by driving the entire apparatus with an XY table; and in the second type of apparatus, the collet is raised and lowered by driving the entire apparatus with a cam. Accordingly, in these apparatuses the weight of the moving components is large, and it is not possible to convey the collet at high-speed. As a result, the conventional apparatuses are in lack of productivity.